• Functional neurological disorders (FND) are unintentional and involuntary. 
• Imaging and electrophysiological studies have shown cerebral dysfunctions in attention and perception, which may explain why symptoms often improve with distraction. 
• Diagnosis requires demonstration of inconsistency and/or incongruency with recognized neurological or medical conditions. 
  • No clinical sign alone is diagnostic. 
  • Patients may have comorbidities such as multiple sclerosis, stroke, or epilepsy. 
• Hoover’s sign and drift without pronation have been described as positive signs for FND. 
  • These can also be seen in patients with pain, neglect, or apraxia. 
• Avoid maneuvers that may harm the patient, such as dropping their arm onto their face. 
  • A high-pitched tuning fork applied to the nostrils is an effective stimulus to assess responsiveness.  
• Avoid using terms like non-organic, psychogenic, or pseudoseizure. 
• When counseling a patient, avoid only explaining what conditions they do not have or attributing symptoms to psychological problems or stress. 
  • Instead, name the diagnosis, explain that their symptoms are real and common, and emphasize that symptoms are potentially reversible. 
• Early diagnosis of FND is associated with improved physical and psychological outcomes. 

Bottom Line: Functional neurological disorders (FND) are commonly encountered in the ED. A thorough neurological exam may reveal positive signs suggestive of FND. Early diagnosis and referral to specialists may improve outcomes. 

References

Finkelstein SA, Cortel-LeBlanc MA, Cortel-LeBlanc A, Stone J. Functional neurological disorder in the emergency department. Acad Emerg Med. 2021 Apr 18 [Online ahead of print] 

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